Non-lethal discarding device



Oct. 22, 1963 J. J. BRADY NON-LETHAL DISCARDING DEVICE Filed Aug. 1, 1962 Center of 3 Gruvtty of Segments Longitude! Axis of Projectile Rotation Resultant Pres.

High LOW fNVENTOR.

JAMES J. BRADY j/zfiwi Q4.

ATTORNEY- Unite States 1 atent 3,197,615 NGN-LETHAL DESARDENG BEVE CE James 3;. Brady, i hiladelphia, Pan, assignor to the United States of America as represented by the Secretary of the Army Filed Aug.

3 CLSllES. (Si. 192-38) (Granted under Title 35, US. Code (1952}, see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to sabots such as are utilized to support small caliber-ammunition in a large caliber gun barrel and to prevent the escape of propellant generated gas past the small caliber proiectile. These sabots consist of a plurality of segments which separate radially at high speeds after their emergence from the gun barrel, such separation being effected by the muzzle gas and air forces acting on them. The force with which these segments are dispersed are sufliciently high to produce serious injury to personnel. The present invention provides a sabot segment which is so formed that its speed is automatically reduced to a non-lethal value.

The present invention will be better understood from the following description when considered in connection with the accompanying drawings and its scope is indicated by the appended claims.

Referring to the drawings:

FIG. 1 is a sectional view indicating the relation between the various parts of the invention,

FIG. 2. is a View taken on the line 2-2 of FIG. 1,

FIG. 3 is an end view of one of the segments,

FIG. 4 is a side view of FIG. 3, and

FIGS. 5 and 6 are explanatory diagrams relating to the design of the segments.

FIG. 1 shows a large caliber cartridge case lb which encloses a propellant ll and has at its breech end a primer 12. At its forward end, the cartridge case it is reduced and in this reduced section are a plurality of sabot segments 13 within which is supported a small caliber projectile 14.

The sabot assembly as constructed and utilized consists of forty segments 13 clustered about the projectile lid and retained by matching buttress grooves 15 in the projectile and buttress teeth 16 in the sabot segments (FIGS. 2 and 4). The cartridge case 1! is crimped into a groove 17 on the outside circumference of the sabot assembly to lock the assembly in position on the projectile. An obturator 1% is located between the propellant ill and the segments 13.

When the cartridge is fired, th sabot assembly and the projectile are accelerated and move from the cartridge case into the gun bore, the propellant gases being sealed behind the sabot by the obturator. After they emerge from the gun muzzle, the se ments are dispersed radially by the muzzle gas wd air forces to which they are subjected. These forces are very considerable. As a result, there is danger of injury to personnel either from a direct hit or the falling of a segment. How this danger is avoided will appear upon consideration of FIG. 5 upon which the calculated form of the sabot segments is based.

The letters appearing in PEG. 5 are defined as follows:

D=outside diameter of sabot d=inside diameter of sabot i location of center of gravity of sabot segment n=number of segments per assembly =angle subtended by one segment R=radius of inner curve of segment r=radius of outer curve of segment 3,lh7,6l Patented Get. 22, Th6? The geometry of the sabot segment is determined from D, d and n as follows:

R and r are tangent at X. pends on R.

These segments are so shaped that they rotate about their longitudinal axes as they travel downwardly. As a result, they have a higher air drag than when they fall endwise. This higher air drag reduces the terminal velocity of the segment to a point where its terminal energy is well below the minimum lethal energy of 58 foot pounds. As indicated by FIG. 6, the shape of the segment is such that the air pressure over it acts on a point other than its center of gravity and the segment is rotated by this pressure about its center of gravity.

This invention is believed to be a pioneer in the field of making sabot segments while falling freely, and after being released, less lethal by slowing their velocity by having an increased air drag attained through rotation of each segment about the center of gravity of the segment as an axis. As shown in FIG. 6, the concave portion rotates in a clockwise direction as indicated by the arrow to the left of the FIG. 6.

I claim:

1. A catridge case having therein a projectile, a propellant, a primer, sabot segments on a central portion of said projectile, and an obturator between said segments and said propellant, there being at least about 40 segments each having radially curved side walls of a shape to enhance air drag of the individual segments during their free fall after leaving the gun muzzle, and causing rotation of each segment about a radial distance through its center of gravity, each radial side face of each segment being provided with a concave and convex portion with the transition occurring at the same radial distance on each side from a longitudinal axis of the projectile occurring on an arc drawn through the center of gravity of said projectile.

2. A combination according to claim 1 in which each segment is held against longitudinal slip by means of buttress type projections and recesses engaging a surface of the projectile.

3. A combination according to claim 2 in which the case is provided with a forward end portion of smaller diameter than that of the major portion of the case length and thesaid forward end portion being provided with a The rotational velocity deperipheral groove extending into said segments.

References Cited in the file of this patent UNITED STATES PATENTS 3,005,409 Dunlap et al Oct. 24, 1961 3,033,116 Critcher et al May 8, 1962 

1. A CARTRIDGE CASE HAVING THEREIN A PROJECTILE, A PROPELLANT, A PRIMER, SABOT SEGMENTS ON A CENTRAL PORTION OF SAID PROJECTILE, AND AN OBTURATOR BETWEEN SAID SEGMENTS AND SAID PROPELLANT, THERE BEING AT LEAST ABOUT 40 SEGMENTS EACH HAVING RADIALLY CURVED SIDE WALLS OF A SHAPE TO ENHANCE AIR DRAG OF THE INDIVIDUAL SEGMENTS DURING THEIR FREE FALL AFTER LEAVING THE GUN MUZZLE, AND CAUSING ROTATION OF EACH SEGMENT ABOUT A RADIAL SIDE FACE OF EACH SEGMENT BEING PROVIDED WITH A CONCAVE AND CONVEX PORTION WITH THE TRANSISTION OCCURING AT THE SAME RADIAL DISTANCE ON EACH SIDE FROM A LONGITUDINAL AXIS OF THE PROJECTILE OCCURRING ON AN ARC DRAWN THROUGH THE CENTER OF GRAVITY OF SAID PROJECTILE. 